Structural and phase transition of mg doped on mn site in la0 7sr0 3mno3 bulk nanostructured perovskite characterised through online ultrasonic technique

Accepted Manuscript Structural and phase transition of Mg-doped on Mn-site in La0.7Sr0.3MnO3 bulk/ nanostructured perovskite characterised through online ultrasonic technique Somasundaram Praveenkumar, Kathiresan Sakthipandi, Mathu Sridharpanday, Mohanraj Selvam, Arumugam Karthik, Srinivasan Surendhiran, Nallaiyan Palanivelu, Gurusamy Raj kumar, Venkatachalam Rajendran PII: S1026-9185(16)30024-5 DOI: 10.1016/j.sajce.2016.12.001 Reference: SAJCE 15 To appear in: South African Journal of Chemical Engineering Received Date: 23 May 2016 Revised Date: 21 November 2016 Accepted Date: 19 December 2016 Please cite this article as: Praveenkumar, S., Sakthipandi, K., Sridharpanday, M., Selvam, M., Karthik, A., Surendhiran, S., Palanivelu, N., Raj kumar, G., Rajendran, V., Structural and phase transition of Mg-doped on Mn-site in La0.7Sr0.3MnO3 bulk/nanostructured perovskite characterised through online ultrasonic technique, South African Journal of Chemical Engineering (2017), doi: 10.1016/ j.sajce.2016.12.001 This is a PDF file of an unedited manuscript that has been accepted for publication As a service to our customers we are providing this early version of the manuscript The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain ACCEPTED MANUSCRIPT TITLE: Structural and phase transition of Mg-doped on Mn-site in La0.7Sr0.3MnO3 bulk/nanostructured perovskite characterised through online ultrasonic Manuscript ID: SAJCE_2016_42 Name Institution Somasundaram Bharathiar University, Praveenkumar (First Coimbatore author) Kathiresan Sakthipandi Email ID praveen@nic.in SC S No RI PT technique K S Rangasamy College of sakthipandi@gmail.com Mathu Sridharpanday M AN U Technology, Tiruchengode K S Rangasamy College of sritech20@gmail.com Technology, Tiruchengode Mohanraj Selvam K S Rangasamy College of selvamic@gmail.com Technology, Tiruchengode Arumugam Karthik K S Rangasamy College of akarthikaru@gmail.com TE D Technology, Tiruchengode Srinivasan Surendhiran K S Rangasamy College of surendhar93phy@gmail.com Technology, Tiruchengode EP Nallaiyan Palanivelu Gurusamy Raj kumar AC C Arignar Anna Government drpalanivelu@gmail.com Arts College for Men, Namakkal Easwari Engineering dr.g.raajkumar@gmail.com College, Chennai Venkatachalam Rajendran K S Rangasamy College of (Corresponding author) Technology, Tiruchengode veerajedran@gmail.com ACCEPTED MANUSCRIPT Structural and phase transition of Mg-doped on Mn-site in La0.7Sr0.3MnO3 bulk/nanostructured perovskite characterised through online ultrasonic technique Somasundaram Praveenkumar1, Kathiresan Sakthipandi, Mathu Sridharpanday, Mohanraj Selvam, Arumugam Karthik, Srinivasan Surendhiran, Nallaiyan Palanivelu2, RI PT Venkatachalam Rajendran* and Gurusamy Raj kumar3 1,* M AN U SC Centre for Nano Science and Technology, K S Rangasamy College of Technology, Tiruchengode - 637215, Tamil Nadu, India Department of Physics, Arignar Anna Government Arts College for Men, Namkkal-637 002, Tamil Nadu, India 1Research and Development Centre, Bharathiar University, Coimbatore - 641046, Tamil Nadu, India Department of physics, Easwari Engineering College, Chennai – 600 089, Tamil Nadu, India Abstract Bulk and nanoshaped perovskite manganite materials were blended to form samples of La0.7Sr0.3Mg1-xMnxO3 (LSMMO) with x = 0.05, 0.075, and 0.100 employing solid state and sonochemical methods, respectively The well-formed LSMMO component was characterized TE D by comprehensive characterization techniques and rhombohedral structure was observed The mean size of the bulk and nano LSMMO manganite perovskites ranges between 260–850 nm and 23–86 nm, respectively The structural and phase transition of the manganite perovskites EP are explored by on-line ultrasonic velocity and attenuation measurementsbetween 300 and 400 AC C K A deliberate change in the ultrasonic velocity, attenuationand elastic moduli shows an abnormal behavior with temperature in perovskites and was associated with the occurrence of ferromagnetic-paramagnetic (FM-PM) transition temperature (TC) In addition, the shifts in TC magnitude and width by increase in x are used to study the etiquette of TC and the change in the nanostructure of the bulk perovskites Keywords: Abnormal behavior; Ultrasonic measurements; Phase transition; Elastic properties; perovskites ACCEPTED MANUSCRIPT *Corresponding author Tel.: +9142882747414, 274880 Fax: +914288274870 (direct), 274860 E-mail address:veerajendran@gmail.com (V Rajendran) Introduction RI PT The existence of colossal magnetoresistance (CMR), ferromagnetic (FM)-paramagnetic (PM) transition, and metal–insulator (MI) phase transitions [1–3] in R1-xAxMnO3 (R-trivalent rare earth atom and A-divalent alkaline metal) perovskites culminates in significant anomalous SC magnetic and transport properties The canonical type La1−xSrxMnO3 (LSMO) perovskites has the double-exchange (DE) interactions along with Jahn–Teller (JT) distortions in the MnO6 M AN U octahedron (Mn atom is the center) The DE interaction and JT distortion is necessary to obtain the large magnetoresistance effects near the phase transition temperature [4, 5] The literature indicates that the role of Mn atom on manganite perovskite is outstanding due to its wide application,catches the attention of comprehensive research [6, 7] TE D Several efforts have been made to examine the CMR associated with the lattice deformation and charge ordering (CO) of the crucial Mn–O–Mn network by doping the divalent alkaline atoms such as Ca, Sr, Ba, and Pb [8–10] at the A-site in the manganite EP perovskite It has been revealed that the magnetic and transport properties of manganite perovskites are devastated by the substitution of Mn at the B-site by any other atom [11–14] AC C The substitution on Mn-site affects the Mn3+–Mn4+ ratio and hence, the exchange interaction of Mn3+–Mn4+occurs The mismatch of ionic radius between Mn and substituted ions has an impact on the lattice parameters of the crystal structure Minorchange in Mn-O bond length and Mn-O-Mn bond angle in Mn3+–O–Mn4+ network [15, 16] produces large variation in the magnetic and transport properties of manganite perovskite Hence, the modification of Mn3+ and Mn4+ ratio generates the change in electron carrier density of Mn–O–Mn network ACCEPTED MANUSCRIPT Although, the stable state of Mg is Mg2+ (6 co-ordinations) having radius of 0.86 Å, which is larger than the radius of Mn3+ (0.645 Å) and Mn4+ (0.53 Å) [15] Doping of Mg2+replaces the Mn in manganite perovskite consequence an expansion of the unit cell than a reduction In the present investigation, we found that, the upshot of substituting Mn by Mg on RI PT the structural and FM-PM phase transition properties of La0.7Sr0.3Mn1−xMgxO3 manganite perovskite with 0.050 ≤ x ≤ 0.100 The in-situ ultrasonic velocity/attenuation measurement is one of the exceptional and SC constructive methods for the comprehensive characterization of LSMMO manganite perovskites The interaction between ultrasonic waves and the coupling in manganite M AN U perovskites, results a change in lattice Any alteration occurring in the lattice degrees of freedom are reflected in the ultrasonic parameters like velocity and attenuation Hence,ultrasonic parameters discovers [17, 18] the FM-PM phase exchangeof any manganite perovskites TE D In this paper, solid state and sonochemical reaction methods are used to produce the Mgdoped bulk and nanoLSMMO(0.050 ≤ x ≤ 0.100) manganite perovskite, respectively The structural as well as the magnetic properties of LSMMO manganite perovskites are revealed EP employing different characterisation techniques Anorganized examination of bulk and nano AC C LSMMO perovskites samples isdone by in-situ ultrasonic measurement Experimental 2.1 Synthesis of La0.7Sr0.3Mg1-xMnxO3manganites The bulk and nano LSMMOmanganite perovskites with different values of x (0.050, 0.075 and 0.100) were formed by solid state [19] and sonochemical reaction process [20] Lanthanum nitrate (99.999%; Sigma-Aldrich, USA), strontium nitrate (99.9%; Sigma-Aldrich, USA), magnesium nitrate (99.0%; Himedia GR, India) and manganite carbonate (99.9%; Sigma-Aldrich, USA) were used to prepare the samples by stoichiometric ratio using similar ACCEPTED MANUSCRIPT procedures used elsewhere [21, 22] Different compositions of manganite perovskites (La0.7Sr0.3Mg0.950Mn0.050O3, La0.7Sr0.3Mg0.925Mn0.075O3, and La0.7Sr0.3Mg0.90Mn0.10O3), named in its bulk (hereafter termed as BLSMMO050, BLSMMO075, and BLSMMO100) and nano samples (hereafter termed as NLSMMO050, NLSMMO075, and NLSMMO100) were RI PT prepared 2.2 Density The density of bulk and nanoLa0.7Sr0.3Mg1-xMnxO3perovskite manganites was SC measured by liquid displacementmethod (Archimedes principle) with CCl4acts as buoyant The digital balance (Sartorius, Germany) was employed to evaluate the weight of prepared manganites [23] ρ= M AN U perovskite manganitesin air (Wa) and in buoyant (Wb) The density of the perovskite Wa ρb W a − Wb (1) 2.3 X-ray diffraction TE D where ρb is the density of the buoyant The density was measured with percentage error ± 0.05 The well-formed manganite perovskite structural investigationwas carried out using X- EP ray diffractometer (X’Pert PRO; PAN Analytical, the Netherlands), CuKα as radiation source (λ= 1.5406Å) with a constant voltage (40 kV) and current rating (30 mA) in the scan range from 10 to 80˚ The relative atomic position of atoms and the crystallite size (DXRD) of bulk and AC C nano La0.7Sr0.3Mg1-xMnxO3 perovskite manganites are estimated with Rietveld’s and Scherrer’s equations [24, 25] 2.4 Microscopic studies The morphology and topography of the prepared perovskite manganites was examined using Field Emission Scanning Electron Microscope (FE-SEM) coupled with X-rays Energy Dispersive Spectrum (EDX) (FEI Nova-Nano SEM-600, The Netherlands) The size of particles and its morphology were measured through Transmitting Electron Microscope (TEM, ACCEPTED MANUSCRIPT CM200, Philips, USA) operated at 120 kV 2.5 Surface area The Specific Surface Area (SSA) of La0.7Sr0.3Mg1-xMnxO3 manganites were obtained through The Autosorb-1 (Quantachrome, USA) surface area analyzer under N2 atmosphere RI PT Manganite perovskites are stay away from the thermally produced changes by degassed the samples under vacuum at 568 K for h so as to remove the redundant gas molecules and moisture[26] SC 2.6 Ultrasonic velocities and attenuation Transmission and reception of ultrasonic waves, by through transmission technique,in M AN U the manganite perovskites wasachieved usinghigh-power ultrasonic Pulsar Receiver (Olympus NDT, 5900 PR, USA) and high-frequency (1 GHz) Digital Storage Oscilloscope (Lecroy, Wave Runner 104 MXi, USA) The MHz X-cut and Y-cut transducers were used to generate the longitudinal and shear ultrasonic waves (heating rate of 0.5 K min-1) The measurements TE D were carried out [21, 22] with temperature from 300 to 400 Kusing the experimental set-up designed in the author’s laboratory and the standard method [27] is employed to carry out the error due to couplant correction EP Results and discussion AC C 3.1 Structural, elemental and surface area analysis The X-ray diffraction image of the prepared LSMMO manganite perovskites is depicted in Fig 1.The image illustrates all samples are in single phase rhombohedral perovskite structure, agrees with the observed peak positions indexed for La0.70Sr0.30MnO3 (JCPDS 50-0308) [28, 29] Substituting Mg ion in the place of Mn maintains rhombohedral structure and only a distortion in the MnO6octahedra is produced at Mn site The average crystallite sizes (DXRD) of the prepared LSMMO manganite perovskites are calculated from the full-width at half-maximum (FWHM) (β1/2) of the diffracted peaks using the Scherrer’s ACCEPTED MANUSCRIPT equation [30], i.e., DXRD=0.94λ/ (β1/2cosθ), where λ is the X-ray wavelength and θ the diffraction angle The crystallite sizes of the bulk manganite perovskite are 476, 511, and 627µm for the Mg content x = 0.050, x = 0.075, and x = 0.100 respectively, on the contrary the crystallite size of nano manganite perovskite are 44, 63, and 87 nm for the composition x = RI PT 0.050, x = 0.075, and x = 0.100, respectively A notable point is that the crystallite size is directly proportional to the content of Mg in bulk and nano manganite perovskites Lattice cell parameters (a, c) and unit cell volume are calculated (Table 1) to investigate SC the structural changes in the bulk and nano LSMMO manganite perovskites [31, 32] and found that it varies with the content of Mg The obtained average Mn–O bond lengths (dMn–O) and M AN U Mn–O–Mn bond angles (θMn-O-Mn) of LSMMO shows (Table 1) that there is a gradual increase in average bond length while it decreases up to x = 0.10 of the average bond angle It is interesting to note that an increase in Mn-O bond length in nano manganite perovskites leads to an overlap between the closest orbits of Mn ions and the nearest O ions The DE interactions TE D in nano manganite perovskites between Mn3+ and Mn4+ ions via O2+ becomes weak than in the corresponding bulk manganite perovskites [33] Thus, the subsequent bulk sample is higher than that of the FM-PM phase transition temperature (TC) of nanoperovskites EP The tolerance factor for the Mg doped La0.7Sr0.3MnO3 Perovskite for different AC C compositions (x = 0.05, 0.075 and 0.100) are obtained using the Goldschmid’s equation [34] The tolerance factor for the LSMMO perovskite is 0.8548, 0.8540, 0.8532 respectively for x = 0.05, 0.075 and 0.100 The values obtained for LSMMO perovskite manganite materials is almost same as the undoped La0.7Sr0.3MnO3 (Tolerance factor = 0.8564) EDX spectra of bulk and nano LSMMO manganite perovskites are shown in Fig It is obvious from the EDX spectra that these manganite perovskites are composed of La, Sr, Mn, Mg, and O atoms The atomic ratio of the constituent elements derived from the EDX pattern is ACCEPTED MANUSCRIPT given in Table and the values are in agreement to the starting content of bulk and nano manganite perovskites Further, the no emission line confirms the absence of impurities in bulk and nano manganite perovskites The surface area values for the bulk LSMMO manganite perovskites are 2.75, 2.43, and RI PT 2.18 m2 g-1, respectively, for x = 0.050, x = 0.075, and x = 0.100, whereas those for nano samples are 24.61, 22.96, and 21.44 m2 g-1, respectively, for x = 0.050, x = 0.075 and x = 0.100 With an increase in Mg content in bulk and nano manganite perovskites, a decrease in SC the surface area is noticed The equivalent spherical diameter (DBET) of bulk and nano LSMMO manganite perovskites is calculated using the formula whereρ is the density of the sample ρ S BET M AN U DBET = (2) It is observed from the lower surface area (Table 1) of bulk LSMMO manganite TE D perovskites, the number of atoms at the surface of nano LSMMO manganite perovskites is more than that of the corresponding bulk sample and hence, large proportions of atoms will be either at or near the grain boundaries of the surface [35] EP 3.2 Microscopic studies Figures 3–5 [i - vi] show SEM and TEM images of bulk and nano LSMMO manganite AC C perovskites, respectively The spherical-like morphology with definite grain boundaries of manganite perovskite particles is observed from the SEM images SEM and TEM images (Table 1)demonstratean increase in the particle size of bulk and nanoLSMMO manganite perovskites with an increase in Mg content from x = 0.050 to x = 0.100 and it is confirmed by characterization studies The circular lines in Selected Area Electron Diffraction (SAED) of LSMMO manganite perovskites(Fig 4) are crystalline in nature ACCEPTED MANUSCRIPT The density values measured at room temperature are 6475, 6433, and 6376 kg m-3 for the bulk manganite perovskites BLSMMO005, BLSMMO075, and BLSMMO100 respectively, and 6417, 6390, and 6359 kg m-3 for the nano manganite perovskites NLSMMO005, NLSMMO075, and NLSMMO100 respectively This denotes that an increase RI PT in the Mg content, the density of LSMMO decreases XRD analysis infers that with an increase in the Mg content in manganite perovskites, the volume of the unit cell increases which leads content [36] 3.3 Velocities and attenuations through ultrasonic studies SC to lose packing of the manganite perovskites Hence, density decreases with an increase in Mg M AN U The temperature dependent ultrasonic velocity and attenuation values are used to reveal the phase transitions and its behavior during the aging of the manganite perovskites The ultrasonic velocity and attenuation along with the derived elastic constant values are presented in Table The ultrasonic velocity (longitudinal and shear)increases with increase of Mg TE D content in a particular temperature The anomalous behavior in the temperature dependent ultrasonic parameters confirms existence of phase transitions at TCin manganite perovskites [37, 38] The temperature dependent longitudinal velocity (UL), shear velocity (US), EP longitudinal attenuation (αL) and shear attenuation (αS) are respectively shown in Figs 5-8 AC C The non-linear variation in velocity/ attenuation is the consequence of structural or phase transition occurs in the perovskites [17, 18] The observed dip in velocity and a peak in attenuation in manganite perovskites are correlated with FM and PM transition temperature The initial and finaltemperatures, exhibiting anomalous behaviors, of the bulk and nano LSMMO samples are presented in Table The whole range of temperature (300–400 K) of each manganite perovskite is categorized into three regions, namely, Region I (from 300 K to the temperature at which anomalous behavior starts, i.e., 364 K for BLSMMO005, 361 K for BLSMMO075, 354 K for BLSMMO100, 350 K for NLSMMO005, 346 K for NLSMMO075 ACCEPTED MANUSCRIPT Figure captions: Fig XRD pattern of bulk and nano LSMMO Fig EDX pattern of bulk and nano LSMMO manganite perovskites Fig SEM photographs of bulk and nano LSMMO manganite perovskites RI PT Fig TEM images of bulk and nano LSMMO manganite perovskite Fig Temperature dependence of longitudinal velocity of BLSMMO and NLSMMO perovskite samples SC Fig Temperature dependence of shear velocity of BLSMMO and NLSMMO perovskite samples M AN U Fig Temperature dependence of longitudinal attenuation of BLSMMO and NLSMMO perovskite samples Fig Temperature dependence of shear attenuation of BLSMMO and NLSMMO perovskite samples Fig Temperature dependence of first differential of longitudinal velocity of BLSMMO and AC C EP TE D NLSMMO perovskite samples AC C EP TE D M AN U SC RI PT ACCEPTED MANUSCRIPT Fig XRD pattern of bulk and nano LSMMO RI PT ACCEPTED MANUSCRIPT ii) NLSMMO005 TE D M AN U SC i) BLSMMO005 iv) BLSMMO075 AC C EP iii) BLSMMO075 v) BLSMMO100 vi) NLSMMO100 Fig EDX pattern of bulk and nano LSMMO manganite perovskites AC C EP TE D M AN U SC RI PT ACCEPTED MANUSCRIPT Fig SEM photographs of bulk and nano LSMMO manganite perovskites AC C EP TE D M AN U SC RI PT ACCEPTED MANUSCRIPT Fig TEM images of bulk and nano LSMMO manganite perovskite RI PT ACCEPTED MANUSCRIPT 6100 5900 SC 5300 5100 BLSMMO050 BLSMMO075 4900 BLSMMO100 TE D 4700 M AN U 5500 NLSMMO050 NLSMMO075 4500 4300 4100 295 305 EP NLSMMO100 315 325 AC C Longitudinal velocity (ms-1) 5700 335 345 355 365 375 385 395 Temperature (K) Fig Temperature dependence of longitudinal velocity of BLSMMO and NLSMMO perovskite samples 405 RI PT ACCEPTED MANUSCRIPT M AN U 2650 BLSMMO050 2350 BLSMMO100 NLSMMO050 EP NLSMMO075 TE D BLSMMO075 NLSMMO100 2050 295 AC C Shear velocity (ms-1) SC 2950 305 315 325 335 345 355 365 375 385 395 Temperature (K) Fig Temperature dependence of shear velocity of BLSMMO and NLSMMO perovskite samples 405 ACCEPTED MANUSCRIPT 2.8 BLSMMO075 BLSMMO100 2.6 NLSMMO050 2.5 SC NLSMMO075 M AN U NLSMMO100 2.4 2.3 TE D 2.2 2.1 1.9 295 305 EP 315 325 AC C longitudinal attenuation (dB.cm -1) 2.7 RI PT BLSMMO050 335 345 355 365 375 385 395 Temperature (K) Fig Temperature dependence of longitudinal attenuation of BLSMMO and NLSMMO perovskite samples 405 ACCEPTED MANUSCRIPT 10.5 RI PT BLSMMO050 BLSMMO075 10 BLSMMO100 9.5 SC NLSMMO075 NLSMMO100 M AN U 8.5 7.5 295 305 315 EP TE D 325 AC C shear attenuation (dB.cm -1) NLSMMO050 335 345 355 365 375 385 395 Temperature / (K) Fig Temperature dependence of shear attenuation of BLSMMO and NLSMMO perovskite samples 405 ACCEPTED MANUSCRIPT RI PT 100 M AN U SC 50 295 350 -50 BLSMMO075 BLSMMO100 NLSMMO050 NLSMMO075 NLSMMO100 -150 -200 EP -100 TE D BLSMMO050 AC C First differential of longitudinal velocity (ms-1 K-1) 150 Temperature (K) Fig Temperature dependence of first differential of longitudinal velocity of BLSMMO and NLSMMO perovskite samples 10 405 ACCEPTED MANUSCRIPT Sample Studies Parameters Bulk samples composition x = 0.050 x = 0.075 x = 0.100 a (A ̊) 5.4861 5.4832 5.4821 c (A ̊) 13.2637 13.2737 Volume (A ̊ 3) 345.755 Nano samples composition x = 0.050 x = 0.075 x = 0.100 5.5041 5.4989 5.4947 13.2759 13.3552 13.3341 13.3180 345.674 345.585 350.408 349.191 348.266 M AN U SC Lattice Parameters XRD RI PT Table Comparison of bond length, bond angle and particle size with characterization studies Mn-O bond Length (nm) 1.9463 1.9470 1.9478 1.9502 1.9510 1.9537 XRD Mn-O-Mn bond angle (˚) 165.97 166.15 166.56 166.59 166.70 166.76 XRD Crystallinity size (nm) 511 627 44 63 87 BET Equivalent Spherical diameter (nm) 336.96 383.82 431.66 37.99 40.90 44.01 SEM Particle size (nm) 258-490 381-645 490-826 23-44 41-67 58-86 TEM Particle size (nm) 234 751 836 21.2 47.4 81.7 AC C EP 476 TE D XRD 11 ACCEPTED MANUSCRIPT Table Elemental EDX compositions of BLSMMO and NLSMMO perovskite samples Element Bulk composition Nano composition x = 075 x = 100 x = 050 La 0.698 0.699 0.698 0.699 Sr 0.3 0.299 0.299 0.299 Mn 0.95 0.925 0.900 Mg 0.049 0.075 0.100 O 2.999 3.000 12 x = 100 0.699 0.300 0.298 SC 0.7 0.95 0.925 0.900 0.050 0.075 0.100 3.000 2.999 M AN U AC C EP TE D 3.000 x = 075 RI PT x = 050 2.999 ACCEPTED MANUSCRIPT Table Measured density and ultrasonic parameters at room temperature (300 K) Bulk composition Parameters x = 0.050 Density (kg m-3) x = 0.075 x = 0.100 6376 UL (m s-1) 5974.35 6040.67 US (m s-1) 2802.479 αL (dB cm-1) x = 0.075 x = 0.100 6417 6390 6359 6144.25 5623.22 5798.25 5852.72 2846.372 2899.40 2687.49 2747.974 2813.085 1.99246 1.9524 1.917021 2.1408 2.0693 2.0166 αS (dB cm-1) 8.13097 7.8353 7.6412 8.7736 8.45568 8.20584 L (GPa) 231.111 234.738 240.706 202.909 214.830 217.823 G (GPa) 50.854 52.119 53.600 46.347 48.253 50.322 K (GPa) 163.306 165.246 169.239 141.113 150.492 150.728 E (GPa) 138.215 141.483 145.445 125.322 130.782 135.847 10 Poisson’s ratio 0.3573 0.3568 0.3520 0.3552 0.3498 TE D EP AC C 0.3589 SC 6433 M AN U 6475 x = 0.050 RI PT S.No Nano composition 13 ACCEPTED MANUSCRIPT Table Temperature range of the region Region-I, Region - II and Region-III of BLSMMO and NLSMMO perovskite manganite materials along with the height and width of the observed anomaly measured from longitudinal velocity Temperature (K) Bulk composition x = 0.100 x = 0.050 x = 0.075 x = 0.100 Start 300 300 300 300 300 300 End 364 361 354 346 342 Start 364 361 354 350 346 342 Anomaly (TC) 368 364 357 356 351 345 End 371 367 359 363 355 348 Start End 13 371 367 359 363 355 348 400 400 400 400 400 400 AC C III 350 EP Width (∆TC) SC x = 0.075 M AN U II Nano composition x= 0.050 TE D I RI PT Region 14 ACCEPTED MANUSCRIPT Highlights: • Anomalous behaviour of magnetic materials has been investigated through high temperature ultrasonic measurement from bulk to nano (La0.7Sr0.3Mg1-XMnO3) Phase transition and structural assessment is merely dominant in nano than bulk magnetic RI PT • materials Elastic modulus namely bulk, young’s modulus and first order derivative is determined as EP TE D M AN U SC a function of temperature AC C • ... TITLE: Structural and phase transition of Mg- doped on Mn- site in La0. 7Sr0. 3MnO3 bulk/ nanostructured perovskite characterised through online ultrasonic Manuscript ID: SAJCE_2016_42 Name Institution... Structural and phase transition of Mg- doped on Mn- site in La0. 7Sr0. 3MnO3 bulk/ nanostructured perovskite characterised through online ultrasonic technique Somasundaram Praveenkumar1, Kathiresan Sakthipandi,... NLSMMO075, and NLSMMO100 perovskites again confirm the phase TE D transition temperature TC Diminishing DE interaction, reduction in CMR and decrease in TC applications Conclusions EP of the Mg doped